1. Field of the Invention
The present invention relates to a method of tilting rolled sections, for example billets, about their longitudinal axes into an on-edge position or diamond pass position. The method utilizes a device which includes a frame that is moveable transversely of a roller conveyor for transporting the billets, and a roller head with pivoting drive equipped with clamping rollers for clamping a billet and pivotable about an axis extending parallel to the longitudinal axis of the billet, wherein the roller head grasps the billet during the longitudinal conveyance thereof and tilts the billet by a predetermined angle before the billet enters a following station.
The present invention also relates to the device for tilting rolled sections, particularly for carrying out the method according to the present invention.
2. Description of the Related Art
When processing billets into light sections or wire, it is frequently necessary to introduce a billet emerging from a furnace on a roller conveyor into the groove of the first stand of the light section or wire mill in the so-called diamond pass position. In order to make this possible, a device for tilting the billets is usually arranged between the furnace and the first stand, wherein the device can also be called a device for placing billets in an upright position.
A device of this type known in the art has, for example, two rollers which are rotatably mounted in a frame. One of the rollers is usually mounted so as to be stationary, while the other roller is adjustable. The frame can be pivoted together with the two rollers by means of a special drive in the plane of the two roller axes about an angle of 45.degree.. Before a billet enters this device, the adjustable roller is lifted up from the stationary roller to such an extent that the billet can move unimpededly between the two rollers. As soon as the billet is located between the two rollers, the adjustable roller is once again lowered, so that the billet is guided between the rollers. By switching on the drive provided for the frame, the frame is now pivoted by an angle of 45.degree. and the billet is positioned by the two rollers into the diamond pass position in which the billet can enter the first stand of the light section or wire mill.
DE-OS 25 33 287 describes a device for tilting billet-shaped rolling stock, wherein the device includes two positioning rollers arranged at a distance and parallel to each other, wherein one of the rollers is mounted so as to be stationary and the other roller is adjustable. When travelling through the rolls, the rolling stock is tilted by means of truncated cone-shaped rollers about an edge, wherein the entering billet presses the adjustable roller against the restoring force of a spring into a passage position.
This device has the disadvantage that the rolling stock is conveyed at rolling heat by the truncated cone-shaped rollers in the diamond pass position, so that the rolling stock is deformed at opposite edges and, thus, is damaged.
DE-AS 1 028 960 describes a gripping-type tilting device whose gripping jaws are mounted in a guide means so as to extend parallel to each other and are adjustable relative to the rolling stock, wherein the guide means is arranged so as to be pivotable about the edge axis in a carriage that is moveable transversely of the rolling direction. The guide means extends continuously on both sides of the edge axis, so that the gripping jaws are adjustable relative to each other by a conventional clamping device acting on the gripping jaws and are freely moveable together with clamping means over the entire guiding range. In the case of an asymmetrical position, the rolling stock is centered with the guide means, wherein impermissible bending stresses cannot be excluded.
Because the rolling stock is clamped from both sides, local deformations may occur which leave visible traces during further processing. Moreover, the device is comparatively complicated with a large number of individual elements and, therefore, is susceptible to trouble and requires maintenance when subjected to scale and other impurities during the rolling stock transportation. A tilting angle of more than 45.degree. cannot be achieved with this device.
DE-OS 27 42 439 discloses another device for tilting billets, wherein the device includes pairs of gripping units, for example, roller pairs, which are adjustable relative to rolling stock surfaces and arranged preferably between the furnace and the first roll stand of a rolling train. The gripping units are arranged at an end of a pivoting lever whose pivot axis is located in the longitudinal axis of the rolling stock and whose at least two pivot points are connected through parallel linkages to two or more additional levers so as to be pivotable, wherein the pivot axes are arranged in a common plane with the longitudinal axis of the rolling stock, and wherein the parallel linkages extend parallel to this plane.
This device has the disadvantage that after tilting has been effected another positioning of the rolling stock into the roll stand must be carried out which requires a vertical adjustment and additional displacement units. The pivot levers provided in a parallelogram arrangement with, for example, eight points of articulation, result in a complicated construction; in addition, also in this device, tilting of a billet by more than 45.degree. cannot be carried out.
Finally, DE OS 1 527 714 discloses a tilting device for rolling stock in which a mechanism couples the force of gravity with a clamping force which is supposed to prevent an impermissible opening of the clamping roller during tilting. This has the result that the clamping force is increased in the case of heavy rolling stock which, in turn, may lead to high surface pressures and local deformations of the rolling stock.